Process for obtaining a renewable hydrocarbon stream suitable as a component of gasoline formulations, renewable hydrocarbon stream, and gasoline formulation

ABSTRACT

The invention relates to a process that comprises dehydration of by-products from ethanol production from sugar cane, by fluidized bed catalytic cracking, for obtaining a renewable hydrocarbon stream, preferably consisting primarily of olefins with 5 carbon atoms, for use in gasolines, and to the and to the hydrocarbon stream and gasoline formulations thus obtained.

FIELD OF THE INVENTION

The present invention relates to a process for obtaining a renewablehydrocarbon stream for use in gasoline formulations, and to thehydrocarbon stream and gasoline formulations thus obtained.

BACKGROUND OF THE INVENTION

The debate concerning eventual exhaustion of the natural reserves ofpetroleum, as well as the need to reduce the level of emissions fromvehicles with internal-combustion engines, have promoted interest in thedevelopment not only of vehicles that are more efficient, but also inresearch into new environmentally friendly fuels and catalyticconverters. Therefore the use of renewable components is an increasinglyfrequent requirement in various segments of the fuels industry.

Renewable fuels, also known as biofuels, are fuels of biological origin.They are made from biomass such as maize, soya, sugar cane, castor seed,canola, palm oil or hemp.

The advantage of using biofuels is associated with the significantreduction in emissions of greenhouse gases compared to fuels derivedfrom petroleum, as well as being a source of renewable energy. The mainbiofuels known at present are alcohol (ethanol), mainly produced fromsugar cane and maize; biogas, produced from biomass; bioether, andbiodiesel, among others. Biofuels may be used alone in vehicles or mixedwith fossil fuels.

Among the biofuels mentioned above, ethyl tert-butyl ether (ETBE) andethanol are products available in Brazil and are examples of biofuelsthat are widely used in gasoline formulations.

Gasoline is a fuel consisting basically of hydrocarbons and, in minoramounts, oxygenates such as alcohols and ethers, which are added to itat the distributors. These hydrocarbons are usually aromatic, olefinic,naphthenic and paraffinic and generally “lighter” than those that makeup diesel oil, as they are formed by molecules with a shorter carbonchain, normally from 5 to 10 carbon atoms.

Depending on the application, the content of oxygen-containingcomponents is limited by the product specification else they affect theproperties of the fuel, mainly in relation to consumption andperformance, due to the lower energy content of the oxygen-containingcomponents relative to the hydrocarbons.

Besides the hydrocarbons and the oxygenates, gasoline may also containsulphur compounds, compounds containing nitrogen, as well as additivesfor various purposes, among which we may mention detergents and depositcontrol additives. Therefore the chemical composition of gasoline iscomplex and may be subject to variations. As a rule, its boiling pointis relatively low, which favours its use as a fuel. Furthermore, itscombustion releases a very good potential amount of energy and its priceis economically viable.

More particularly, automotive gasoline is created from various streams,called naphthas, arising from various refining processes. These naphthasdiffer from one another in respect of the types and contents ofhydrocarbons that they contain, depending on the refining processes thatproduce them, which accounts for the variation in the constitution ofgasoline.

Various processes may be used for obtaining gasoline from petroleum. Therefining processes undergo continuous evolution simultaneously withprogress in engine design. With design changes, mainly in respect of thecompression ratio, for increase in power, the refiners improve themanufacturing processes for gasoline in order to satisfy the qualityrequirements, which are becoming more and more demanding. At the sametime, higher consumption of gasoline has led to the development ofprocesses giving higher yields. These objectives have led to the currentstate of the petroleum refining industry, constituting one of the mostefficient and complex technologies.

The main processes used for production of gasoline are fractionaldistillation, vacuum distillation, thermal or catalytic cracking andcatalytic reforming.

Cracking, which is widely used, consists of breaking long hydrocarbonmolecules of high molecular weight into others with a shorter chain andlower molecular weight. It is an extremely important processindustrially that makes it possible to obtain, from a single compound,various compounds with smaller molecules, which are used for variouspurposes.

Cracking may be thermal or catalytic. Thermal cracking is carried out athigh temperatures and pressures. For example, to transform molecules inthe kerosene distillation range, diesel oil or lubricating oil, intogasoline, the temperatures used are between 450° C. and 700° C. However,catalytic cracking does not require high temperatures and pressures,owing to the use of catalysts, making the process safer and moreeconomical.

To assess the quality of gasoline, a property called octane number, alsoknown as octane rating, is measured, which indicates the knockresistance on compression of the fuel.

In the octane rating scale, index 100 is ascribed to isooctane(2,2,4-trimethylpentane; C₈H₁₈), for which knock only occurs at highcompression ratios, and index zero to n-heptane (C₇H₁₆), for which knockoccurs at very low compression ratios.

The octane number of a gasoline informs that this fuel possesses knockresistance equivalent to that of a mixture of isooctane and n-heptanewith a volume percentage of isooctane numerically equal to the octanenumber, when analysed in a standard engine. For example, a gasoline withan octane rating of 80 has knock resistance equivalent to that of amixture of 80% v/v of isooctane and 20% v/v of n-heptane.

The relationship between organic compounds and octane rating obeys thefollowing rules:

-   -   branched alkanes have a higher octane number than the        corresponding normal alkanes;    -   cycloalkanes have a higher octane number than the corresponding        normal alkanes;    -   alkenes have a higher octane number than the corresponding        alkanes;    -   aromatic hydrocarbons have a very high octane number.

The higher the octane rating of a gasoline, the higher its knockresistance. Some components or even finished gasolines have an octanerating above 100, requiring the use of other standards for determiningthe octane rating, such as isooctane with addition of standardizedcontents of tetraethyl lead or aromatic compounds of known octanerating.

The octane rating is one of the most important parameters of gasolinequality, and is directly related to the performance of the product.However, other properties are important for performance, such assuitable volatility characteristics, combustion rate compatible with theapplication, and energy content sufficient to guarantee power andautonomy.

The availability of a gasoline stream that combines all of its optimizedparameters in one and the same product, such as octane rating,combustion rate and energy content (calorific value), is still achallenge both from the technical and from the commercial standpoint.

From the above discussion it is clear that there is still a current needto obtain gasoline streams with properties that are more attractive fromthe standpoint of performance, especially higher calorific value,starting from renewable raw materials, to fill gaps in performance leftby the renewable products currently available, for exampleoxygen-containing components (ethanol, ETBE, etc.).

In this connection, the attention of research and development teams hasbeen directed towards obtaining these products from alternative biomasssources, especially with upgrading of by-products from processes thatalready exist.

Fusel oil, for example, is a residue/by-product obtained from fuelethanol distilleries, consisting of a mixture of higher alcohols, suchas isoamyl alcohol (IAA), isobutyl alcohol, among others. These alcoholsare classified as congeners of alcoholic fermentation and must beremoved in the rectification column, as they tend to accumulate in theunit. In countries where fuel ethanol is produced on a large scale, suchas Brazil, alternatives for utilization of the residues generated inthis process would be of great importance for making ethanol productionless polluting and more profitable. The low price of fusel oil and itshigh content of isoamyl alcohol, coupled with the high volume of fuseloil produced in Brazil annually, would justify the development oftechnologies that require the use of this mixture.

Thus, there are various documents that describe processes such as thosereferred to above for obtaining automotive gasoline of renewable originstarting from these by-products. However, no processes have beendeveloped that combine adaptation of refining technologies with the useof fusel oil or IAA as raw materials.

Document WO2013/169461, for example, describes a process for theproduction of olefins and aromatic hydrocarbons, in which a feed thatcomprises an oil from biomass pyrolysis, or a fraction thereof, issupplied to a steam cracking plant at a temperature from 600 to 1000°C., or a reverse flow reactor operating at a temperature from 900 to1700° C., and one or more fractions of hydrocarbon effluents areproduced by thermal cracking. However, the high temperatures andpressures employed in this cracking process mean it is not veryeconomical and safe, and is therefore unattractive.

Document US2012/0220808A1 describes a process for the production oflong-chain olefins at high yield and high selectivity by submittinglong-chain primary aliphatic alcohols to a liquid-phase dehydrationreaction. The term “liquid-phase reaction”, as used in the invention,signifies that the reaction is conducted at a temperature not above theboiling point of the raw alcohol, that is, at a temperature not abovethe temperature at which a liquid phase of the alcohol is still present.

However, there is still a need to develop a process for obtaining arenewable hydrocarbon stream consisting primarily of light olefins foruse in the production of gasolines with properties that are moreattractive from the standpoint of performance, particularly with highercalorific value.

As will be presented in greater detail below, the present invention aimsto solve the problems of the prior art described above in a practicaland efficient manner.

SUMMARY OF THE INVENTION

The present invention relates to a process for obtaining a renewablehydrocarbon stream suitable as a component of gasoline formulations,using by-products from ethanol production from sugar cane as rawmaterial, and to the hydrocarbon stream and gasoline formulations thusobtained. The invention is defined in the claims.

According to a first aspect of the disclosure, there is provided aprocess for obtaining a renewable hydrocarbon stream suitable as acomponent of gasoline formulations, characterized in that it comprisesone or more of: a) a dehydration reaction of a feed of by-products fromethanol production from sugar cane based on the technology of fluidcatalytic cracking (FCC) in the presence of an optionally pulverizedacid catalyst, at temperature and pressure in the range 350-550° C. and0 kgf/cm² (0 KPa) to 2 kgf/cm² (196.13 KPa), respectively, wherein thecatalyst/feed ratio used varies between 3 and 10; and b) distillation ofthe liquid product obtained in step a) at a temperature in the rangefrom 20 to 70° C., preferably from 20 to 50° C., obtaining a hydrocarbonstream consisting primarily of olefins with 5 carbon atoms, wherein thedegree of conversion of the by-products from ethanol production fromsugar cane into olefins with 5 carbons is in the range from 80 to 100%.

The liquid product obtained in step a) can be cooled before continuingto the distillation step b).

The by-product from ethanol production from sugar cane can be fusel oil,and more preferably the isoamyl alcohol present therein.

The stream of olefins obtained in step b) can comprise a percentage ofisoamylenes between 60 and 80%.

The temperature of the dehydration reaction can be in the range 450-500°C.

Tthe pressure of the dehydration reaction can be in the range from 1kgf/cm² (98.07 KPa) to 1.8 kgf/cm² (176.52 KPa).

The pulverized acid catalyst can be alumina, silica-alumina, zeolite Yand/or mixtures thereof.

The catalyst/feed ratio can be between 4 and 8.

The degree of conversion of the by-product from ethanol production fromsugar cane into olefins with 5 carbons can be in the range from 90 to100%.

According to a second aspect of the disclosure there is provided arenewable hydrocarbon stream, characterized in that it is obtained bythe process as discussed in connection with the first aspect.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure relates to a process for obtaining a renewablehydrocarbon stream for use in gasolines, using by-products from ethanolproduction from sugar cane as raw material.

In particular, this disclosure deals with a process for obtaining arenewable hydrocarbon stream, preferably by means of a dehydrationreaction of a by-product from ethanol production from sugar cane,particularly fusel oil and, more preferably, isoamyl alcohol presenttherein, bearing in mind the availability of these by-products on alarge scale in Brazil. Said process is based on cracking technology ofthe fluidized bed catalytic cracking type (fluid catalytic cracking,FCC), which allows continuous and prolonged operation of the process inthe vapour phase, using existing refinery equipment (dispensing with theuse of a dedicated reactor) for obtaining a hydrocarbon streamconsisting primarily of light olefins containing 5 carbon atoms.

The fluidized bed catalytic cracking process can employ suitable,commercially available catalysts that preferably include pulverized acidcatalysts and, more preferably, alumina, silica-alumina, zeolite Yand/or mixtures of any or all of these components. The catalyst/feedratio used in said dehydration reaction, which corresponds to the flowrate by weight of the feed (isoamyl alcohol or fusel oil) and catalystcirculation, can vary between 3 and 10, preferably between 4 and 8.

The reaction can take place at temperatures in the range from 350 to550° C., preferably between 450 and 500° C. The operating pressures forthe reaction are those typical of a fluidized bed catalytic crackingprocess (FCC) and can vary between about 0 kgf/cm² (0 KPa) and 2 kgf/cm²(196.13 KPa), preferably between 1 kgf/cm² (98.07 KPa) and 1.8 kgf/cm²(176.52 KPa).

The aforementioned operating conditions are selected so as to promotemaximum conversion of the by-products from ethanol production from sugarcane into hydrocarbons containing mainly branched olefins with 5 carbonatoms, also known as isoamylenes. At the same time the reactionconditions avoid the formation of by-products from cracking andcondensation such as Liquefied Petroleum Gas (LPG) (3 and 4 carbonatoms) and aromatics, such as benzene, toluene and xylenes, which aresecondary products of octane rating and have lower calorific value. Ingeneral, the values of the degree of conversion of isoamyl alcohol toolefins with 5 carbons are in the range from 80 to 100%, preferablybetween 90 and 100%, and give rise to a light naphtha of excellentquality.

The liquid product obtained from the dehydration reaction is preferablycooled (to prevent loss of the isoamylenes by evaporation) and thendistilled at a temperature in the range from 20 to 70° C., preferablybetween 20 and 50° C., in a TBP (true boiling point) column to separatethe naphtha cut. As mentioned, the degree of conversion of isoamylalcohol is high, above 80%. This can give as the final result, inaddition to other by-products, a stream with a percentage of isoamylenesfrom 60 to 80% w/w, a high octane rating and stability compatible withthe values observed for automotive gasolines. Furthermore, the contentof sulphur and of nitrogen compounds present in the product derived fromfusel oil is compatible for various segments of gasoline, includingproducts that require low contents of impurities.

Therefore, compared to other processes for biomass conversion,dehydration of isoamyl alcohol is superior in maximizing the yield ofthe desired distillation range, and in avoiding the presence ofoxygenates in the final fuel.

The following examples illustrate various embodiments of the presentinvention.

EXAMPLES Example 1—Production of Streams of Isoamylenes at the PilotScale

Preliminary tests for assessing the operating conditions of the FCC werecarried out in a circulating pilot unit. The pilot unit was equippedwith an adiabatic riser with a length of 1 m and an isothermal rectifierand a regenerator with temperature controlled by electric heating. Thecatalyst inventory of the unit was 2 kg and the flow rate of feed was 1kg/h. The catalyst used was Ecat 1, a pulverized catalyst containingzeolite Y, used in a Petrobras commercial FCC unit in the cracking ofgas oil. Table I presents the composition of the Ecat 1 catalyst (andEcat 2, referred to further below), along with the specific area of thecatalyst.

TABLE I Composition and specific areas of Ecat 1 and Ecat 2. ParametersECAT 1 ECAT2 Specific Area m²/g 153 159.2 Al₂O₃, % w/w 41.8 43.2 Na, %w/w 0.33 0.23 Re₂O₃, % w/w 3.28 2.59 V, mg/kg 1284 544 Ni, mg/kg 12921053 P₂O₅, % w/w 1.00 0.75 Zeolite Y content 40% 40%

A feed of isoamyl alcohol (IAA) of petrochemical origin was used forstudying the effect of the operating conditions, and the fusel oil usedin run 3 was supplied by an ethanol distillery.

Table II presents a summary of the operating conditions of the pilotunit and of the yields of isoamylenes, including the cracking reactiontemperature (TRX), and the catalyst to feed (oil) ratio (CTO). Theoperating conditions were selected so as to optimize the conversion ofIAA, forming isoamylenes by dehydration, and at the same time minimizethe formation of products with secondary octane rating and lowercalorific value. Assessment of the processing of fusel oil was onlyconducted at the pilot scale, with a focus on assessing a lower-cost rawmaterial. The fusel oil used in run 3 contained, based on dry matter,76% w/w IAA (71% 3-methyl-1-butanol and 5% 2-methyl-1-butanol), 6% w/wbutanols and 16% w/w ethanol. Overall, the fusel oil contained 17% w/wof water, resulting in lower yield of isoamylenes and higher yield ofwater compared to the IAA feed (run 1 vs run 3—Table II). To generate asufficient volume of liquid product, runs lasting 3 hours were carriedout. The liquid product was collected in a vessel cooled with dry ice(to prevent loss of the isoamylenes by evaporation) and then distilledin a TBP column to separate the naphtha cut (initial boiling point[IBP]=70° C.), generating a sample of approximately 1 L, sufficient forcomplete characterization.

TABLE II Experimental conditions of the tests for dehydration of isoamylalcohol in the pilot unit. Parameters Run 1 Run 2 Run 3 Feed IAA 99% IAA99% Fusel oil fossil fossil Catalyst Ecat 1 Ecat 1 Ecat 1 TRX, ° C. 350450 350 T. regenerator, ° C 600 600 600 CTO 7.1 7.3 8.4 Conversion IAA,% w/w 88.6 99.0 90.6 Yields, % w/w: — — — Isoamylenes 44.4 49.5 29.1Unreacted alcohol 11.4 1.0 9.4 Aromatics 0.2 0.7 0.5 Other liquid HCs20.8 23.3 15.6 Water 18.9 20.9 38.3 Gas 2.5 3.5 5.5 Coke 1.7 1.1 1.6

Table III presents the data for characterization of the productsgenerated in the pilot unit after distillation, including the lowercalorific value (LCV) and the higher calorific value (HCV), andcomposition measured by gas chromatography (GC). The ASTM testing methodreference for each parameter is included in brackets in the first columnof the table.

It can be seen from Table III that all the cuts are light enough, withlow density and high volatility (measured by RVP—Reid vapour pressure),showing that the process generates a stream with properties compatiblewith those of gasolines.

Regarding the energy content, it is observed that the products derivedfrom processing the 99% fossil IAA had a lower calorific value (LCV) ofabout 44.3 MJ/kg, which is an excellent value, suitable for specialgasoline formulations. The LCV of the product derived from theprocessing of fusel oil was approximately 2.3% less than that of theproducts derived from IAA, and this reflects the presence of therelatively high ethanol content (4.3% w/w) recovered in distillation. Itshould be emphasized that processing of fusel oil proved promising, asthe negative impact observed on the LCV of the TBP cut can be correctedby adjusting the final boiling point (FBP) of the distillation cut (forexample, 50° C.), which eliminates the presence of ethanol (boilingpoint [BP]=78° C.).

TABLE III Data for characterization of the TBP distillation cuts (IBP -70° C.) of the products from dehydration of 99% fossil IAA (runs 1 and2) and of fusel oil (run 3) in the pilot unit. Results Product ProductProduct from run 1 from run 2 from run 3 Vapour pressure @ 37.8° C.115.3 117.6 129.5 (D5191), kPa Density @ 20° C. (D4052) 0.6540 0.65380.6693 FBP distillation (D86), ° C. <70 <70 <70 Induction period (D525),min 175 66 61 (>1.200^(i)) (>1.200^(i)) (>1.200^(i)) Potential gum(D873) — — — Not washed, mg/100 mL 12.5 26.0 30.0 Washed, mg/100 mL 8.5— 28.0 Actual gum (D381) — — Not washed, mg/100 mL <0.5 2.0 <0.5 Washed,mg/100 mL <0.5 — <0.5 HCV (D4809), MJ/kg 47.581 47.432 46.369 LCV(D4809), MJ/kg 44.419 44.339 43.271 Composition by GC (N2377) — — —Saturates, % w/w 21.4 9.5 10.9 Olefins, % w/w 78.1 90.4 84.4 Aromatics,% w/w 0.1 0.0 0.2 Oxygenates, % w/w 0.0 0.1 4.4 Isoamylenes content, %w/w 66.2 72.2 68.1 Benzene, % w/w 0.1 0.0 0.1 H, % w/w (N 2377)^(ii)14.9 14.6 14.6 C, % w/w (N 2377)^(ii) 85.1 85.4 83.9 O, % w/w (N2377)^(ii) 0.0 0.0 1.5 Total sulphur (D7039), — — 20.4 mg/kg Totalnitrogen (D5762), — — 8.7 mg/kg RON (D2699) 99.4^(iii) ND^(iii) ND^(iii)(99.6^(iv)) (99.2^(v)) (101.0^(iv)) ^(i)Value of IP for mixture of 10%w/w component/90% w/w alkylated product (IP alkylated product > 1200min) ^(ii)Calculated from data on composition by GC ^(iii)RON of thepure sample. Sample very volatile, irregular combustion ^(iv)RON valuefor mixture of 10% w/w component/90% w/w alkylated product (RONalkylated product = 98.5) ^(v)RON value for mixture of 10% w/wcomponent/90% w/w alkylated product (RON alkylated product = 96.4)

Regarding the octane rating, it was not possible to measure the RON(research octane number) of the pure products, owing to the highvolatility of the cuts, which upsets the analysis. Only the cut from run1 had its RON estimated at 99.4, showing that the stream has a highoctane rating. Assessment of the octane rating of the products wascarried out with mixtures of each stream with an alkylated product ofhigh isooctane content (80-85% w/w), in the proportion of 10% w/w of thecut generated with 90% w/w of alkylated product. The RON octane ratingof the mixtures compared with the octane ratings of the alkylated baseused in the mixture showed that all the cuts had similar performance,with an intensified effect in the mixture.

Regarding the stability of the products, all the cuts showed values ofactual and potential gum compatible with values observed for automotivegasolines. Regarding the induction period (IP), despite the low valuesof IP of the cuts, the results obtained in mixtures with a more stablestream (alkylated product) were much higher, indicating that they arenot a problem.

Another point that deserves special mention is that the sulphur contentand nitrogen content in the product derived from fusel oil is compatiblefor various segments of gasoline, including products that require lowcontents of impurities. The presence of these contaminants was notassessed in the cuts derived from 99% fossil IAA, since the raw materialused in the tests was not the renewable raw material of interest.

Example 2—Production of a Bioisoamylene Stream on a Semi-IndustrialScale

Production of the isoamylene stream on a semi-industrial scale wascarried out in a prototype FCC unit, equipped with an 18 m riser,adiabatic regenerator and adiabatic stripper. Table IV presents theoperating conditions for obtaining the product. To supply the energyrequired for dehydration of IAA, torch oil was burned in the regeneratorof the unit, maintaining the temperature of the regenerator at thespecified value. The catalyst inventory of the prototype unit was 350kg. Before the production tests, a stream of practically sulphur-freeS10 diesel was processed, to purge the systems of condensation andguarantee sulphur content below 10 mg/kg for the stream. The IAAprocessed in the semi-industrial FCC unit was purified from fusel oilresidue from distillation of sugar-cane ethanol (referred to as“bio-IAA”). The catalyst (Ecat 2), similar to the catalyst used inexample 1, was supplied by a Petrobras refinery. The dehydration productwas collected and separated from the water produced in a pressure vesselat 1 kgf/cm², with the aid of a density sensor, which made it possibleto monitor the water-naphtha interface during emptying of the vessel.The liquid product generated in the FCC unit was then fractionated in adistillation unit to generate the final stream. As it was a productderived from raw material of vegetable origin, the product became knownas “bioisoamylene”.

TABLE IV Operating conditions for production of the bioisoamylene stream(run 1), derived from the dehydration of bio- IAA 99%, obtained on asemi-industrial scale. Parameters Run 1 Feed Bio-IAA 99% (PETROM)Catalyst Ecat 2 TRX, ° C. 450 T. regenerator, ° C. 680 T. feed, ° C. 25Feed flow rate, kg/h 170 CTO 7.4 Conversion of IAA, % 100 w/w Yields, %w/w: — Isoamylenes 52.5 Unreacted alcohol 0.0 Naphtha 68.6 Aromatics 0.0Water 23.6 Gas 6.7 Coke 1.1

Table V shows the data from characterization of the distillation cutgenerated after processing the bio-IAA 99%.

The product had characteristics similar to those of the productsobtained in the pilot plant. Regarding volatility, bioisoamylene wasfound to be somewhat lighter than the product generated in the pilotplant, with higher RVP, resulting from the greater recovery of lightcomponents (compounds with 4 carbons) relative to the products from thepilot plant.

The final product had high calorific value and octane rating (RON>100and LCV=44.8 MJ/kg), compatible with the values observed in the cutsproduced in the pilot plant. Both properties are excellent, indicatingthat bioisoamylene is a suitable stream for use in special gasolineformulations.

TABLE V Data for characterization of the isoamylene stream (run 1),derived from the product of dehydration of bio-IAA 99% on asemi-industrial scale. Tests Results Vapour pressure @ 37.8° C. 130.3(D5191), kPa Density @ 20° C. (D4052) 0.6573 Distillation (D86) — IBP, °C. 23.4 T5%, ° C. 29.0 T10%, ° C. 30.0 T50%, ° C. 33.4 T90%, ° C. 35.4T95%, ° C. 35.8 FBP, ° C. 39.2 Induction period (D525), min 87(>1.440^(i)) Actual gum (D381) — Not washed, mg/100 mL <0.5 Washed,mg/100 mL <0.5 Potential gum (D873) — Not washed, mg/100 mL 12.5 Washed,mg/100 mL 11.5 HCV (D4809), MJ/kg 47.952 LCV (D4809), MJ/kg 44.833 GC(N2377) — Saturates, % w/w 14.9 Olefins, % w/w 85.1 Aromatics, % w/w 0.0Oxygenates, % w/w 0.0 Isoamylenes content, % w/w 63.5 Benzene, % w/w 0.0H, % w/w (N 2377)^(ii) 14.7 C, % w/w (N 2377)^(ii) 85.3 O, % w/w (N2377)^(ii) 0.0 Total sulphur (D7039), mg/kg 8.5 Total nitrogen (D5762),mg/kg 0.8 RON ND^(iii) (100.9^(iv)) ^(i)Value of IP for mixture of 10%w/w component/90% w/w alkylated product (IP alkylated product > 1.200min) ^(ii)Calculated from data on composition by GC ^(iii)Notdetermined. Sample very volatile, irregular combustion ^(iv)RON valuefor mixture of 10% w/w component/90% w/w alkylated product (RONalkylated product = 98.5)

Regarding stability, the product had behaviour similar to that of theproducts of the pilot plant, and it was not necessary to use anantioxidant additive. Furthermore, it should be emphasized that theproduct was easier to produce, as post-treatment unit operations werenot required to ensure stability.

Regarding the content of impurities (total N, total S and oxygen), verylow values were observed, which did not cause any problem for meetingany current specification for all series of gasolines, including thosewith low sulphur content.

In general, the composition of the product, the physicochemical data forbioisoamylene (RVP, density, distillation, LCV and octane rating) andthe data on stability indicated very good suitability of the product asa component of gasolines, since its use may provide all the propertiesrequired for the formulations.

In addition, some properties of bioisoamylene are significantly betterthan those observed for the naphthas obtained by petroleum refining,indicating that this hydrocarbon stream, consisting primarily of olefinswith 5 carbon atoms, tends to contribute to the development of variousspecial gasolines.

As may be deduced from the above examples, the process for dehydrationof by-products from ethanol production from sugar cane based on FCC ofthe present disclosure results in a hydrocarbon stream with a highpercentage of isoamylenes, high octane rating and energy content. Thestability is compatible with the values observed for automotivegasolines and the content of sulphur and nitrogen-containing compoundsis compatible for various gasoline segments. Therefore the product issuitable for various applications, such as development of products withbetter performance (aviation gasoline, premium gasolines, competitiongasolines) or as an octane improver for automotive gasolines.

Numerous variations falling within the scope of protection of thepresent application are permitted. The present invention is not limitedto the configurations/particular embodiments described above.

1. Process for obtaining a renewable hydrocarbon stream suitable as a component of gasoline formulations, characterized in that it comprises: a dehydration reaction of a feed of by-products from ethanol production from sugar cane, using fluid catalytic cracking (FCC) in the presence of an acid catalyst, the dehydration reaction occurring at a temperature in the range 350-550° C. and a pressure in the range of from 0 kgf/cm² (0 KPa) to 2 kgf/cm² (196.13 KPa), and wherein the catalyst/feed ratio by weight is between 3 and
 10. 2. Process according to claim 1, further comprising distillation of the liquid product obtained from the dehydration reaction at a temperature in the range of from 20 to 70° C., preferably from 20 to 50° C.
 3. Process according to claim 2, further comprising obtaining a hydrocarbon stream consisting primarily of olefins with 5 carbon atoms.
 4. Process according to claim 3, wherein the degree of conversion of the by-products from ethanol production from sugar cane into olefins with 5 carbons is in the range from 80 to 100%.
 5. Process according to claim 2, wherein the liquid product obtained from the dehydration reaction is cooled before continuing to the distillation.
 6. Process according to claim 1, wherein the by-product from ethanol production from sugar cane is fusel oil, and more preferably the isoamyl alcohol present therein.
 7. Process according to claim 3, characterized in that the stream consisting primarily of olefins comprises a percentage of isoamylenes between 60 and 80%.
 8. Process according to claim 1, wherein the temperature of the dehydration reaction is in the range 450-500° C.
 9. Process according to claim 1, wherein the pressure of the dehydration reaction is in the range from 1 kgf/cm² (98.07 KPa) to 1.8 kgf/cm² (176.52 KPa).
 10. Process according to claim 1, wherein the acid catalyst is alumina, silica-alumina, zeolite Y and/or mixtures of any or all thereof.
 11. Process according to claim 1, characterized in that the catalyst/feed ratio by weight is between 4 and
 8. 12. Process according to claim 1, characterized in that the degree of conversion of the by-product from ethanol production from sugar cane into olefins with 5 carbons is in the range from 90 to 100%.
 13. Renewable hydrocarbon stream, obtained by the process as defined in claim
 1. 14. Gasoline formulation, comprising the renewable hydrocarbon stream of claim
 13. 